A056634 Number of polygons of length 2n with one hole on square lattice (not allowing rotations).

1, 24, 342, 3804, 36802, 326540, 2735308, 22006264, 171912401, 1313614776, 9868281330, 73150450248, 536495354621, 3900954906412, 28164962681150, 202166363020920, 1444068530799525, 10272599729628876

Offset

8,2

Links

I. Jensen, Table of n, a(n) for n = 8..41 (from link below)

I. Jensen, More terms

Crossrefs

Cf. A002931.

Sequence in context: A264454 A077527 A083766 * A022748 A288968 A269029

Adjacent sequences: A056631 A056632 A056633 * A056635 A056636 A056637

Keyword

nonn

Author

N. J. A. Sloane, Aug 30 2000

Status

approved